The invention relates to a sling for urinary incontinence and to a method of treating urinary incontinence.
In healthy people, muscular tube-like ureters move urine from the kidneys to the bladder, where it is stored until it is convenient to urinate, at which point the urine flows out of the body through the tube-like urethra. A circular muscle, called the sphincter, controls the activity of the urethra.
Stress incontinence is a storage problem in which the urethral sphincter is not able to hold urine. Storage problem may occur as a result of weakened pelvic muscles that support the bladder (seen especially in elderly people), or malfunction of the urethral sphincter. Prior trauma to the urethral area, neurological injury, and some medications may also weaken the urethral closure.
More particularly, an underactive outlet in then may result from a congenital defect or from direct or indirect trauma to the anatomy or physiology of the bladder outlet. Indeed, direct trauma due to prostatectomy is the most common cause of male sphincter weakness.
Stress incontinence may be seen in women who have had multiple pregnancies, pelvic surgery, pelvic prolapse (protrusion of the bladder or urethra into the vaginal space), cystocele, (or rectocele. Additionally, women with low estrogen levels may have stress incontinence due to decreased vaginal muscle tone.
Stress incontinence results in a condition in which patients suffer urine leakage when coughing, sneezing, standing up, lifting objects, or physically exerting themselves. Sufferers may experience not only physical discomfort, but also emotional discomfort. Many people affected by loss of bladder control isolate themselves for fear of embarrassment and ridicule, and the condition is often connected to a loss of self-esteem, with many sufferers being too embarrassed to report the condition or seek medical treatment. Adults also often find employment difficult or impossible because of these factors.
While many sufferers of stress incontinence simply wear a catheter or adult diaper, the applicant is aware of many different surgical procedures that may be used to treat incontinence. Some of the more common procedures performed to treat urinary incontinence include bladder neck suspension or sling procedures, periurethral bulking injections (for example, collagen injections around the urethra injections of other material and injections of balloon-like structures), anterior vaginal repair or implantation of an artificial urinary sphincter.
Many of these procedures have potentially serious complications, for example, potential complications that can occur alter a collagen injection include infection, urine retention, and temporary erectile dysfunction in men. Some people may also have a potentially serious allergic reaction to collagen. Some of the procedures also require substantial invasive surgery, which is not only expensive but is also potentially harmful for the patient undergoing the surgery. Invasive surgery is again required if the continence of the patient later changes, if the original procedure was insufficient to properly treat the incontinence or if infection necessitates removal of the device. Furthermore, sometimes discomfort experienced by patients having, for example artificial urinary sphincters, is not negligible. Apart from the above factors, the products and procedures are expensive, thereby often limiting the treatment available to many patients.
In the sling procedure mentioned above, a piece of abdominal tissue (fascia) or synthetic material is placed underneath the urethra like a hammock or sling to support and compress it, thus inhibiting urine leakage during stress manoeuvres. The various sling procedures performed all involve placing a sling under the urethrovesical junction and anchoring it to retropubic or abdominal structures or both. These procedures have traditionally been performed on mostly female patients, where the sling is placed between the urethra and vaginal wall.
Severe complications, many of which are directly attributable to local effects of the sling (i.e. infection, erosion of the sling, nonhealing of the vaginal wall in women, abscess and vesicovaginal fistula in women) have been observed. Other possible complications include urinary retention and new onset of irritative voiding symptoms.
A need therefore exists to provide an affordable and simplified device and procedure for treating urinary stress incontinence, which reduces the possibility of complications arising, requires less invasive surgery and which is easier to adjust, especially in men.
Accordingly, according to a first embodiment of the invention there is provided a prosthesis for treating urinary incontinence, the prosthesis including:
a flexible elongate member; and
a distensible portion.
The distensible portion may be located an a surface of the elongate member. The prosthesis may include a conduit, typically a flexible pipe, in flow communication with the distensible portion. A valve means connected to an end of the conduit remote from the distensible portion may be provided, the valve means being in flow communication with the distensible portion.
At least one ridge may be located on an inner surface of the distensible portion. Similarly, at least one longitudinal or spiral ridge may be located along at least a portion of the length of an inner surface of the conduit.
The valve means may be sized and configured to permit subcutaneous implantation thereof in a labial region of a female patient, or in a scrotum of a male patient. The valve means typically includes a housing, a layer of resiliently deformable material; and a protection means for protecting the conduit from penetration by a sharp-object. The resiliently deformable material may be self-scaling, for example, the material may be a silicone rubber. An outer surface of the valve means may contain grooves or ridges.
The sharp object from which the protection means protects the conduit may be a needle, more particularly, a syringe needle. The protection means may be a cone-shaped plate having perforations to permit fluid flow therethrough.
The elongate member, distensible portion and conduit may be manufactured from bio-compatible materials. Similarly, the valve means may be covered with a bio-compatible material
According to a second embodiment of the invention there is provided a method for surgically treating urinary incontinence, the method including the following steps:
inserting a prosthesis dorsally between the urethra and pelvic bone the prosthesis including a flexible elongate member and a distensible portion, and
securing either end of the elongate member to retropubic or ischial structures such that the distensible portion is positioned between the urethra and pelvic bone.
The prosthesis may be a prosthesis substantially of the type described above.
The prosthesis may be positioned such that the distensible portion is located between the urethra and the elongate member, and the elongate member is located between the pelvic bone and the distensible portion. The ends of the elongate member are preferably attached to left and right inferior pubic rami using non-absorbable sutures. The valve means may be subcutaneously implanted in a labial region of a female patient, or in a scrotum of a male patient.
The method may further include the step of distending the distensible portion by injecting fluid, preferably a fluid containing radio-opaque dye, into the distensible portion through the valve means in order to increase pressure exerted by the prosthesis on the urethra. The distensible portion may be distended until the pressure is sufficient so as to substantially constrict the urethra. Fluid may also be extracted from the distensible portion through the valve means so as to decrease the pressure exerted by the prosthesis on the urethra.